▎ 摘　　要

NOVELTY - Synthesis of graphene oxide-manganese-iron composite nano-material involves (i) preparing graphene oxide from graphite powder and sodium nitrate in the presence of sulfuric acid, (ii) subjecting graphene oxide to potassium permanganate oxidation under vigorous agitation at controlled conditions to obtain a pasty reaction mixture with the change of color to light brown, (iii) treating the reaction mixture with water under vigorous stirring and maintaining the temperature at 95-99 degrees C, (iv) stopping the oxidation by cooling the reaction mixture and completion of the formation of fumes by another water addition, (v) adding iron to the reaction mixture in the form of iron sulfate to maintain carbon-manganese:iron ratio of 1:2.5-3.5, and (vi) adjusting the pH of the mixture of 7-8, filtering and washing thoroughly with deionized water and drying the solid. USE - Synthesis of graphene oxide-manganese-iron composite nano-material used as adsorbent material for treating contaminated and impure water for purifying impurities such as arsenic, fluoride and chromium (all claimed). Can also be used for removing lead. ADVANTAGE - The method enables simple, economical, easy to handle and one pot synthesis of graphene oxide-manganese-iron composite nano-material having high surface area in nano pores with highly functionalized open active bonds with ligands such as iron and manganese and excellent adsorbent properties and purification efficiency. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for purification of contaminated and impure water, which involves treating impure water at appropriate conditions with graphene oxide-manganese-iron composite nano-material.